[8u60] Request for approval: JDK-8067344: Adjust java/lang/invoke/LFCaching/LFGarbageCollectedTest.java for recent changes in java.lang.invoke

[Konstantin Shefov]

Hello,

Please approve the direct backport of the test bug fix to 8u60
The webrev is slightly different from that for JDK 9, but only in line 
numbers, all the rest is just the same.

The bug: https://bugs.openjdk.java.net/browse/JDK-8067344
The 8u60 webrev: http://cr.openjdk.java.net/~kshefov/8067344_8u/webrev.00/

JDK 9 changeset: http://hg.openjdk.java.net/jdk9/dev/jdk/rev/75c351a01d3c
Review thread: 
http://mail.openjdk.java.net/pipermail/core-libs-dev/2014-December/030452.html

Thanks
-Konstantin